Rivaroxaban as good as warfarin in AF patients with bioprosthetic mitral valves: RIVER trial

The interesting and breakthrough findings have been put forth in American Heart Association's Scientific Sessions conducted from November 13 to November 17 ,2020.

"This is the largest trial designed to evaluate the safety and efficacy of direct oral anticoagulants in patients with bioprosthetic mitral valves and atrial fibrillation or flutter. Earlier trials of direct oral anticoagulants vs. warfarin for atrial fibrillation or flutter together included fewer than 200 patients with bioprosthetic mitral valves," said lead study author Otavio Berwanger, a cardiologist and epidemiologist, and the director of the Research Institute Hcor, Heart Hospital .

The RIVER trial followed 1,005 patients from 49 sites in Brazil who had a bioprosthetic mitral valve and atrial fibrillation or flutter for 12 months. Patients were randomized to rivaroxaban 20 mg once daily or the vitamin K antagonist anticoagulant warfarin (dose-adjusted to an international normalized ratio (INR) between 2.0-3.0). The primary endpoint was a composite of death, major cardiovascular events (stroke, transient ischemic attack, systemic embolism, valve thrombosis or hospitalization for heart failure) or major bleeding over 12 months.

A major finding highlighted that Patients who received rivaroxaban had an average of almost one year (347.5 days) free from the primary endpoint, similar to those treated with warfarin (340.1 days).

On further subgroup analysis of 18.8% of RIVER patients with bioprosthetic mitral valve implantation within the prior three months showed a mean of 35.1 days longer without evidence of the primary outcome compared to patients treated with warfarin.

"Additionally, our confidence interval likely excluded an effect size larger than 1.4 days free from events favoring warfarin, clearly demonstrating the non-inferiority effect of rivaroxaban in this clinical setting," the team quoted.

For full article follow the link: https://newsroom.heart.org/news/rivaroxaban-may-be-as-effective-as-warfarin-for-bioprosthetic-mitral-valves-af?preview=809957187cbbd683538afd4ab019a7a1